Papermaking machine forming member



Jan. 5, 1965 w. u. DAY

PAPERMAKING MACHINE FORMING MEMBER 2 Sheets-Sheet 1 Filed March 22, 1961 $9 PA /0A ART A I z I 1/ Jan. 5, 1965 Filed March 22, 1961 III I |ll|l|l|||| llllllllllllllll' l ULJUUUULJULJLL! lllllllllllllllll- W. U. DAY

PAPERMAKING MACHINE FORMING MEMBER 2 Sheets-Sheet 2 United States Patent M My invention relates to papermaking machines, particularly of the Fourdrinier type, and more particularly to improved Fourdrinier fabrics for use in such machines.

Fourdrinier fabrics for forming a web such as of paper,

by drainage of water from paper stock applied onto the a the fabric, are commonly woven with warp strands extending in the machine direction (that is in the direction in which the Fourdrinier fabric is moved as stock is applied onto the fabric), interwoven with shute strands extending in the cross machine direction. The weaving process is necessarily quite time consumin and expensive due to the fact that each of the shute strands must pass between various ones of the warp strands and each shute strand must be put into place individually.

It is an object of the present invention to provide an improved web forming fabric, particularly for Fourdrinier machines, which is very much simpler in construction and, therefore, considerably cheaper to manufacture than the conventional woven fabrics. I t

More particularly, it is an object of the present invention to provide an improved Fourdrinier forming fabric.

comprising shute strands which are simply laid on the warp strands on one side of the fabric and are bonded to the warp strands in such positions.

Still more particularly, it is an object of the invention to provide an improved fabric of this type which has various of the strands crimped, so that the fabric is more generally in a single plane; and it is also an object to provide an embodiment ofthe invention in which the shute strands extend slantwise with respect to the warp'strands.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects, and such other objects, as will be. apparent from, the followingdescription of preferred forms of the invention, illustrated with reference to the accompanying drawings, wherein:

PEG. 1 is a side view, partially schematic, of. a- Fourdrinier web forming machine including a Fourdrinier forming fabric movably trained in the form of a loop about a plurality of supporting rolls and including'a stock inlet for applying stock onto the fabric;

FIG. 2 is a longitudinal sectional View on an enlarged scale of the stock inlet; 7

FIG. 3 is a fragmentmy plan view of a forming fabric for use inthe machine illustrated in FIGS. 1 and 2;

FIG. 4 is a transverse sectional view of the forming invention.

Like characters of reference designate like parts in the several views. 1

Referring now to the drawings, the illustrated paperi as of brass or bronze and may be of the same or different I V diameters; and at the points of crossover of the strands Patented Jan. 5, 1965 belt .10. The headbox 16 may be of any suitable type, but is preferably one that is particularly suitable for pressure forming. As shown, it comprises a stock turbulizing driven roll 18 disposed in a cylindrical cavity 19. A stock inlet conduit 20 is connected to the cavity 19, and a throttle plate 21 is adjustably positioned adjacent the roll 18 within the conduit. The slice 17 is provided with an apron plate 22 and a lip 23, and the belt 10 extends around the breast roll 11 and in contact with the lip 23 as shown particularly in FIG. 2.

Referring to FIG. 3, the fabric 10 may be made up'of a plurality of warp strands or filaments 50 which extend in the machine direction, that is, in the direction of movement of the fabric 10, and a plurality of shute strandsor filaments 51 which extend in the cross machine direction. The strands 56 are equally spaced from each other, and the strands 51 are likewise equally spaced from each other, although, it will be understood that the strands 50 may be spaced from eachother at different distances than the strands 51. The strands 51 in the illustrated form of fabric extend at right angles to the strands 50; and the strands 51 all overlie all of the strands 50, so thatthe strands 51 are on the papermaking side of the cloth 1t) and come into contact with the lip 23 as the cloth 10 moves.

The strands 5t) and 51 may be round metal wires, such adhesives such as nitrile rubber, Thiokol rubber, Thiokol epoxy mixtures, epoxy resin or urethane polymers.

Due to the fact that the transversely extending strands 51 are elevated with respect to the strands 50 extending in the machine direction, the stock fibers applied onto the fabric 16 in the forming region between the lip 23 and 1 the apron 22 tend to turn parallel with thetransversely extending strands 51, and the resultant web is one that has an increased strength transversely as compared to webs thatare formed on conventional woven wires that have both the warp and shute strands substantially in the same plane. The elevated transversely extending strands 51 have another advantageous function, namely, of providing a scraping action on the end of the lip 23, so as to assure that there is no undue accumulation of fibers behind the lip 23 with resulting poor and uneven sheet formation.

If desired, the fabric 10 may be used in reversed condition so that the strands 50 extending in the machine direction are now on the papermaking side. In this case, the'transversely extending strands 51 are on the underside and contact the various rolls 11, 12, 13and 14 carrying the fabric as well as the suction box 15. The strands 51 in the cross direction are 'notunder tensile stress due to being looped about these rolls; and, therefore, there is not the same tendency for Wear to occur on them. The

making machine may be seen. tbcomprise an endless fabric used in this manner may thus advantageously be expected to have a longer life.

A modified form of fabric belt is illustrated in FIG. 5

-in which the strands 56a extending in the machine direc- FIG; 6 is a cross sectional view, corresponding to FIG. 4, in that the view is taken transversely of the fabric, and this view shows a modified'forming fabric having transversely extending strands 52 which are crimped between the longitudinally extending strands 53 and into the plane of the strands 53 to form a fabric which is generally more in a single plane. It will be understood that 'this view can also be a sectional view taken longitudinally of the fabric, and in this case the strands 52. are strands extending longitudinally of the fabric and are crimped. In the case in which the crimped strands 52 extend in the cross machine direction, this form of fabric may be expected to provide a web that has a lower cross directional strength than the web formed by the fabric illustrated inor the other of the cloth' illustrated in FIG. 6 may be used as the papermaking side as desired. These forms of fabric can be made by first bonding straight wires together to form a fabric of the type illustrated in FIG. 3, and the wires 52 and 53 may then be crimped. The crimping may be used to control the machine direction strengthcross direction strength ratio of the resulting web, and, in

the case in which the strands 53 are crimped and extend in the machine direction on the underside, the machine direction strength may be expected to be higher and longitudinally extending light basis weight stripes may also be expected;

FIG. 7 illustrates a modified form of Fourdrinier fabric in which the strands 54- extending in the cross machine direction are not exactly perpendicular to the strands 55 extending in the machine direction. The strands 54 reams strands and extending in the machine direction. In this case, either the set of strands 55 or the set of strands 57 contact the lip 23 and extend in the same direction as the lip.

Although the strands of the cloths above described have been illustrated to be round, I contemplate that they may very well be square or rectangular in cross section as illustrated in FIG. 9. In this modified form of frabric, the strands 59 and 6d are both rectangular in cross section; and, thus, flat surfaces of the strands 59 are in contact with flat surfaces of the strands 6% so that better joints, particularly if the joints are spot welded together, may be expected between the strands. As is obvious, the cloth may be formed so that the strands 59 are either on the papermaking side or on the undeside, and the strands 59 may extend either in the machine direction or in the cross direction.

FIG. 10 illustrates a modified form of cloth made up of strands of rectangular cross section and similar otherwise to the FIG. 6 fabric, the strands 61 being crimped between the strands'62. The strands 62 may also, if desired, be crimped between the points of cross over with the strands 61. The fabric shown in FIG. 10 may be used in the same ways as the FEGQG fabric.

It will be understood that the cross laid fabrics illustrated in FIGS. 5, 6, 7, 8, 9 and 10 may have their strands fixed together in the same manners as has been described for the strands of the form of fabric shown in FIGS. 3

rather extend in a slanting direction, at an acute angle,

ing each other.

' and 4. It will also be understood that it is not necessary,

for each of the forms of fabric above described, to bond every one of the cross-over points of the strands cross- Only enough of these points of intersection may be bonded to hold the strands together sufiiciently well so that the strands do not separate in use.

I wish it to be understood that the invention is not to be limited to the specific constructions and arrangements shown and described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art that changes may be made without departing from the principles of the invention.

I claim:

1. An endless fabric belt for Fourdrinier type papermaking machines which is adapted to be supported by to form a paper web on the belt, said belt comprising a purpose of controlling the machine direction/ cross direc-' tion strength ratio, and the wires 54; or 55'may also be this purpose in particular. Assuming that the cross direction strands 54 are used on the papermaking side, the

disposition of the strands 54 slantwise with respect to the machine direction also advantageously assures that the I stress applied on the cross direction strands 54, due to the rubbing action by the lip 23 on them, is minimized.

' As will be apparent, the transverse strands54 pass obliquely under the lip123 with the two ends of each strand passing under the lip at different times with one end leading the other, and points between the two ends progressively pass under the lip, so that the lip isnot effective on all points of the strand at once in an action tending to shear crimped as are the wires in the FIG. 6 form of fabric for a first set of filaments extending parallel to each other and longitudinally of the belt and a second set of filaments all disposed on the same side of the belt and extending parallel to each other'and crosswise of the belt in contact with and all at a certain angle to the filaments of said first set, the filaments of each of said sets being equal in diameter and being equally spaced and the filaments of said two sets being bonded together at intersections of the filaments. V i

2. A fabric belt for Fourdrinier type papermaking 7 machines as set forth in claim 1 in which said two sets of tending in the machine direction and a set of shute strands and extending in the machine direction, the belt may be formed with the strands 58 being used as warp filaments extend substantially at right angles with respect to each other.

3. A fabric belt for Fourdrinier type papermaking machines as set forth in claim 1 in which said two sets of filaments extend at acute angles with respect to each other.

4. A fabric belt for 'Fourdrinier type papermaking machines asset forth in claim land which includes a third set of filaments extending crosswise of the belt and similar to said second set of filaments and disposed on the side of the belt opposite to that on-which said second set of filaments is located. i i

5. A fabric belt for Fourdrinier type papermaking machines as set forth in claim 1 in which each of the filaments'of each of said sets is crimped so that it extends between the individual filaments of said other set.

6. A fabric belt for Fourdrinier type papermalring 5 machines as set forth in claim 1 in which said filaments 1,945,890 I are rectangular in cross section. 2,537,323

7. A fabric belt for Fourdrinier type papermaking 2,756,650 machines as set forth in claim 1 in which said filaments 2,796,810 are metallic and in which said filaments are bondedto 5 2,903,021 each other by means of fused metal.

References Cited in the file of this patent 5,647

age 1,514

UNITED STATES PATENTS Perry Jan. 26, 1897 135.

6 Gaskell n. Feb. 6, 1934 Wurzburger Jan. 9, 1951 Lee July 31, 1956 Muller Jan. 25, 1957 Holden Sept. 8, 1959 FOREIGN PATENTS Great Britain A. D. 1828 OTHER REFERENCES Hunter: PaperMaking Through Eighteen Centuries, William Edwin Rudge, New York (1930), p. 214, Fig. 

1. AN ENDLESS FABRIC BELT FOR FOURDRINIER TYPE PAPERMAKING MACHINES WHICH IS ADAPTED TO BE SUPPORTED BY AND TO TRAVEL OVER A PAIR OF SAPCED ROTATABLE ROLLS AND TO RECEIVE AND DRAIN A FLUENT MASS OF FIBERS AND WATER TO FORM A PAPER WEB ON THE BELT, SAID BELT COMPRISING A FIRST SET OF FILAMENTS EXTENDING PARALLEL TO EACH OTHER AND LONGITUDINALLY OF THE BELT AND A SECOND SET OF FILAMENTS ALL DISPOSED ON THE SAME SIDE OF THE BELT AND EXTENDING PARALLEL TO EACH OTHER AND CROSSWISE OF THE BELT IN CONTACT WITH AND ALL AT A CERTAIN ANGLE TO THE FIALMENTS OF SAID FIRST SET, THE FILAMENTS OF EACH OF SID SETS BEING EQUAL IN DIAMETER AND BEING EQUALLY SPACED AND THE FILAMENTS 